I normally wear a small but ordered a medium because I heard it ran small. The collar is a little tighter than I'd expect for a medium, but it's longer than I'd expect for a small. I'd call it more of a S/M than a medium. Everything (including the collar) does stretch nicely, but it might still be a little tight on somebody who's in the larger end of normally wears medium.

I'm a tiny girl, and the small fits me comfortably. It's a little loose, but fits a lot like other small, non-fitted t-shirts I own. It's pretty stretchy, too. The collar is my only gripe. It's a bit small, but stretchy. I'm probably going to make mine into a v-neck anyway.

I normally wear a small but ordered a medium because I heard it ran small. The collar is a little tighter than I'd expect for a medium, but it's longer than I'd expect for a small. I'd call it more of a S/M than a medium.
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I normally wear a small but ordered a medium because I heard it ran small. The collar is a little tighter than I'd expect for a medium, but it's longer than I'd expect for a small. I'd call it more of a S/M than a medium. Everything (including the collar) does stretch nicely, but it might still be a little tight on somebody who's in the larger end of normally wears medium.

Actually, I had a larger friend try mine on and it fit her great. She normally wears a medium or large, depending on the brand. So I'd say that at least the smaller sizes run fairly true to size.

Ok the day they came out I ordered a medium because there were no reviews to tell me, the next day they were on the gift page and I ordered a small figuring I could give it away if it doesn't fit. They both fit, the small is a little snugg but looks great with tight shorts. The medium is great for running around in. I am ordering a large to sleep in so I will have one for every occasion I am normally a small.

I think for smaller women they work, but I ordered a 3x because I'm a big girl and usually a 3x works a little loose on me, but these are impossible. They cannot be a 3x, it wont even fit over my boobs and I am only a 44D. I am thinking of giving mine to my son as a play shirt that he can paint in.

The sizes seem to run a bit small, and I think they run smaller as you go up in size. So the medium I got wasn't incredibly tiny, but was smaller than I expected. The XLs looked pretty small, like a usual size L.